package com.apache.netty.http;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.*;
import io.netty.util.CharsetUtil;

import java.net.URI;

/**
 * 说明 1. SimpleChannelInboundHandler 是 ChannelInboundHandlerAdapter
 *     2. HttpObject 客户端和服务器端相互通讯的数据被封装成 HttpObject
 */
public class TestHttpServerHandler extends SimpleChannelInboundHandler<HttpObject> {

  // channelRead0 读取客户端数据
  @Override
  protected void channelRead0(ChannelHandlerContext ctx, HttpObject msg) throws Exception {

    System.out.println(
        "对应的channel="
            + ctx.channel()
            + " pipeline="
            + ctx.pipeline()
            + " 通过pipeline获取channel"
            + ctx.pipeline().channel());

    System.out.println("当前ctx的handler=" + ctx.handler());

    // 判断 msg 是不是 httpRequest请求
    if (msg instanceof HttpRequest) {

      System.out.println("ctx 类型=" + ctx.getClass());

      System.out.println(
          "pipeline hashcode"
              + ctx.pipeline().hashCode()
              + " TestHttpServerHandler hash="
              + this.hashCode());

      System.out.println("msg 类型=" + msg.getClass());
      System.out.println("客户端地址" + ctx.channel().remoteAddress());

      // 获取到
      HttpRequest httpRequest = (HttpRequest) msg;
      // 获取uri, 过滤指定的资源
      URI uri = new URI(httpRequest.uri());
      if ("/favicon.ico".equals(uri.getPath())) {
        System.out.println("请求了 favicon.ico, 不做响应");
        return;
      }
      // 回复信息给浏览器 [http协议]
      ByteBuf content = Unpooled.copiedBuffer("hello, 我是服务器", CharsetUtil.UTF_8);

      // 构造一个http的相应，即 httpResponse
      FullHttpResponse response =
          new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.OK, content);

      response.headers().set(HttpHeaderNames.CONTENT_TYPE, "text/plain");
      response.headers().set(HttpHeaderNames.CONTENT_LENGTH, content.readableBytes());

      // 将构建好 response返回
      ctx.writeAndFlush(response);
    }
  }
}
